Patient's Expectations, Preferences, Experiences Before, During and After the Treatment With Invisalign® Aligners

Orthodontic treatment extends over a longer period of time. lt takes months or rather years and it is no short-term treatment. The current literature does not answer the question of patients' expectations on aligner treatment and patients' experiences during aligner therapy sufficiently. Therefore, it is clinically and ethically highly relevant to know answers to these questions. This knowledge can highly improve the orthodontic consultation and therapy as well as the patients' comfort and wellbeing during the therapy. The proposed questionnaire-based interview survey is anticipated as a two-vear study.

In the first year study patients' expectations and preferences before the aligner treatment with Invisalign® aligners will be evaluated as well as preliminary changes in quality of life during the first stages of the Invisalign® aligner treatment. In the second year study it is planned to continue with the time equivalent questionnaires of the first year study and to investigate the patients' expectations, patients' experiences and levels of quality of life during and after aligner treatment. Therefore, it is planned to enroll 55 patients in this multicentre questionnaire-based interview survey. Two different questionnaires will be handed out to the patients. The first questionnaire, the aligner questionnaire, collects information from three different time points regarding the patients' expectations, preferences, experiences and views on second opinion concerning the aligner treatment. The results of those three time points, i.e. first (Ta0 before treatment begin), second (Ta6Mo, after 6 months of treatment) and third (Ta final, after finishing the treatment) will be statistically described and compared over time.

We expect most questionnaires of the second (during aligner treatment) and third time points (after finishing of treatment) to be evaluated by the end of the second year (second-year study), as the average treatment duration is about two years. The aim of the second questionnaire (OHlP 14) is to find out the changes in quality of life and is scheduled be started already in the firsfyear study. This questionnaire will be handed out to the patients before the treatment begins (Tq0), at the first check-up after the beginning of the treatment (TqCo1) and semi-annually afterwards (Tq6Mo' Tq12Mo, Tq18Mo, Tq24Mo, Tq30Mo) and finally at the end of the treatment (Tq final).